The present invention relates generally to networks, and more particularly, to a method for detecting devices connected to such a network.
Networks, such as computerized Local Area Networks (LANs) are commonly used to interconnect many different devices, such as computers. There is an increasing requirement to provide communication between these devices. This is because of the number of devices that are to be connected together, and the increases in the amount of information that is to be communicated between them. As a result, a number of networking technologies have been developed, and many standards have been developed around these technologies.
One example of such a technology includes a token ring network in which many devices are connected in either a physical or logical ring, and a token is transmitted around the ring from device to device. When a device requires access to the ring to transmit information, it waits to receive the token and then holds the token while transmitting data on the network. Other devices are prevented from receiving the token while information is being transmitted by the token holder.
Another networking technology is Ethernet. Ethernet is a commonly used LAN scheme in which multiple devices are connected together. In some cases, only one device can transmit data at a time. A device transmits data in the form of a packet that includes a destination address. The packet propagates throughout the network, and is received by all other devices connected to the network. The destination device may copy the entire packet. The other devices may reject the packet after determining that it is addressed to the destination device.
Because of the large number of users and devices associated with a LAN, management of the LAN is quite complex and can be handled by a system administrator or a centralized management system. The system administrator or central management system is an entity that a user of a device typically contacts when the user encounters a problem related to the network. The increasing growth and complexity of LANs makes it more difficult for a user to contact the system administrator. For example, the identity and/or location of the system administrator may not be known to many users. In addition, reliance on these centralized management systems can cause congestion in the LAN due to the number of packets destined to the system administrator. Further, a centralized management system increases the risk of network failure because of the excessive reliance on the system administrator.
In general, in one aspect, the present invention is directed to a method for detecting characteristics of a plurality of peer devices connected to a network that includes generating. an identification frame by one of the peer devices. The identification frame may be propagated to only the other peer devices in the network.
Implementations of the invention include one or more of the following. The identification frame may include a network address or a group address. An error or a predefined MAC address may be introduced into the frame to cause the peer device to recognize the frame. The network may be a token ring or an Ethernet network. The error may be a corruption of the cyclic redundancy control (CRC) check bit or a predefined combination of the padding bits of the identification frame.
In another aspect, the present invention is directed to a computer network that includes a plurality of peer devices connected to the network by a plurality of links and switches. An identification frame is propagated from one peer device to the other peer devices to enable a plurality of features of the peer devices receiving the identification frame.
Implementations of the invention may include one or more of the following. The identification frame may be a MAC frame. The identification frame may be exchanged in a management information format. Each of the switches may have a media access controller connected between the selected device and a transceiver circuit. The transceiver circuit may include a controller for recognizing an error or a predefined MAC address in the identification frame.
In yet another aspect, the present invention is directed to a network including a plurality of peer devices that includes a plurality of switches connected to the devices. The switches may include computer software residing on a computer readable medium at each switch to recognize an identification frame from one of the peer devices. The switch may propagate the identification frame only to other ones of the peer devices in the network.